Polyurea compositions have been used as components of liquid pavement marking compositions, as described in U.S. Pat. No. 6,166,106 to Purgett, et al. The binder of the pavement marking compositions described therein is prepared from a two-part system that includes an amine component and an isocyanate component. The composition described therein contains reflective elements to provide visibility and reflectivity to the pavement markings over an extended length of time. The amine and isocyanate components are chosen to provide a composition that is a liquid with a high solids content, has a generally rapid cure profile with a tack-free time of preferably no greater than about five minutes, and an open time of at least about 30 seconds to allow for adequate substrate wet out and particle or reflective element wicking/anchorage. Preferred amines include aspartic ester amines, as described in column 5, line 43 through column 7, line 10. A wide variety of isocyanates may be utilized in the pavement marking composition, as described beginning at column 7, line 11.
Polyurea spray compositions have also been used as elastomerically coating or lining materials. For example, U.S. Pat. No. 5,405,218 to Hyde-Smith discloses fast curing elastomeric materials that can be applied directly to existing concrete, brick, tile, mortar, and metal surfaces normally found in sewer manholes and catch basins. Similarly, U.S. Pat. No. 6,013,755 to Primeaux II, et al. discloses a method for preparation of polyurea elastomers comprising reacting an amine chain extender with dialkyl maleate to form an aspartic ester, wherein the chain extender has a molar amount of amine groups that is less than the moles of alkyl maleate; blending the aspartic ester with one or more polyoxyalkyleneamines to prepare a resin blend; and contacting the resin blend with an isocyanate under conditions effective to form a polyurea elastomer.